Revenue (Tables)

12 Months Ended

Dec. 31, 2018

Mineral Fiber [Member]

Disaggregation Of Revenue [Line Items]

Schedule of Net Sales by Major Customer Group within Each Segment

The following tables provide net sales by major customer group within the Mineral Fiber and Architectural Specialties segments for the years ended December 31, 2018, 2017 and 2016:

Mineral Fiber	2018		2017		2016
Distributors	$	601.4	$	563.3	$	549.0
Home centers		84.0		82.2		78.7
Direct customers		60.3		62.1		61.9
Retailers and other		55.9		48.8		47.0
Total	$	801.6	$	756.4	$	736.6

Architectural Specialties [Member]

Disaggregation Of Revenue [Line Items]

Schedule of Net Sales by Major Customer Group within Each Segment

Architectural Specialties	2018		2017		2016
Distributors	$	129.8	$	111.5	$	73.4
Direct customers		36.7		22.3		23.9
Retailers and other		7.2		3.4		3.4
Total	$	173.7	$	137.2	$	100.7